Optical limiting effects in linear carbon chains

The nonlinear optical properties of linear carbon chains prepared by laser ablation in water were studied by using a nanosecond pulsed excitation A strong optical limiting response was detected at laser fluences above 0 6 J/cm(2) The nature of the nonlinear effect was investigated by the Z scan technique determining both the nonlinear absorption coefficient beta and the refraction one n(2) A high second order hyperpolarizability gamma value of 1 1 x 10(-29) esu, essentially attributed to a dispersive effect, has been measured Moreover the good optical transparency in the visible region and a relatively good photo-stability make these carbon water colloids comparable with other carbon based materials and interesting for potential applications as optical limiter (C) 2010 Elsevier Ltd All rights reserved